Error conditions in computer power-up and operating procedures are conventionally indicated by one or both of audio tones provided through a speaker and messages written to the screen of a connected video monitor. For example, most basic input output (BIOS) systems for IBM compatible systems are configured to provide a beep tone if a portion of a power on self test (POST) routine is failed. As another example, most computers have pre-stored error messages that are accessed and displayed if certain error conditions are encountered.
Beyond beep tones and pre-stored error messages written to a display, many current art systems make more detailed information available to a user by writing to an I/O port, typically port 0080h. Such detailed information may be accessed by a user by installation of a special expansion card called a POST card. Installation of a POST card, however, requires removing the computer's cover and installing the card in one of the expansion slots typically provided within the computer's body. The installation and configuration of expansion cards is a task beyond the scope of most computer users.
A more user-friendly way to indicate error conditions without the need for additional software or hardware is needed. Such a system could be provided as a part of a computer's BIOS, or an extension of the BIOS, and should use existing hardware for indicating error conditions to a user.